The present invention relates generally to medical devices, methods, and systems. More specifically, the present invention improves the delivery of a therapeutic heating energy that causes tightening, shrinking, and/or debulking of a target tissue, particularly for the noninvasive treatment of urinary incontinence.
Urinary incontinence arises in both women and men with varying degrees of severity, and from different causes. In men, the condition occurs most often as a result of prostatectomies which result in mechanical damage to the sphincter. In women, the condition typically arises after pregnancy where musculoskeletal damage has occurred as a result of inelastic stretching of the structures which support the genitourinary tract. Specifically, pregnancy can result in inelastic stretching of the pelvic floor, the external sphincter, and most often, to the tissue structures which support the bladder and bladder neck region. In each of these cases, urinary leakage typically occurs when a patient's intra-abdominal pressure increases as a result of stress, e.g. coughing, sneezing, laughing, exercise, or the like.
Treatment of urinary incontinence can take a variety of forms. Most simply, the patient can wear absorptive devices or clothing, which is often sufficient for minor leakage events. Alternatively or additionally, patients may undertake exercises intended to strengthen the muscles in the pelvic region, or may attempt behavior modification intended to reduce the incidence of urinary leakage.
In cases where such non-interventional approaches are inadequate or unacceptable, the patient may undergo surgery to correct the problem. A variety of procedures have been developed to correct urinary incontinence in women. Several of these procedures are specifically intended to support the bladder neck region. For example, sutures, straps, or other artificial structures are often looped around the bladder neck and affixed to the pelvis, the endopelvic fascia, the ligaments which support the bladder, or the like. Other procedures involve surgical injections of bulking agents, inflatable balloons, or other elements to mechanically support the bladder neck.
Unfortunately, each of these procedures has associated shortcomings. Surgical operations which involve suturing of the tissue structures supporting the urethra or bladder neck region require great skill and care to achieve the proper level of artificial support. In other words, it is necessary to occlude or support the tissues sufficiently to inhibit urinary leakage, but not so much that intentional voiding is made difficult or impossible. Balloons and other bulking agents which have been inserted can migrate or be absorbed by the body. The presence of such inserts can also be a source of urinary tract infections. Therefore, it would be desirable to provide an improved therapy for urinary incontinence.
One proposed alternative method for treatment of urinary incontinence is described in commonly owned U.S. Pat. No. 6,216,704 B1, the complete disclosure of which is incorporated herein by reference. The proposed method of treating urinary incontinence includes heating and shrinking fascia and other collagenous support tissue in a non-invasive manner to cause the tissue to contract, while minimizing substantial necrosis of adjacent, intermediate tissues. In some embodiments, a plurality of cooled electrodes are used to cool the intermediate tissue and to deliver a therapeutic heating energy to the target tissue.
While the proposed treatment is highly effective, it would be beneficial to better control the temperature of the intermediate tissue that is contacted by the cooled electrodes so as to minimize the damage to the intermediate tissue during delivery of the therapeutic heating energy to the target tissue through the intermediate tissue.